Knock-down load support



y 30} 1939- w. B. CAST KNOCK-DOWN LOAD SUPPORT 'Filed Dec 5, 1938 2 Sheets-Sheet 1 4 INVENTOR. jZ/iam (ea-f;

May 30, 1939. w. B. cAsT KNOCK-DOWN LOAD SUPPORT.

Filed Dec. 3, 1958 2 Sheets-Sheet 2 v INVENTOR 2/4/1421 (2:1,

ATTORNEY 5 Patented May 30, 1939 UNITED STATES PATENT, oFFicE' 2,160,124 KNOCK-DOWN LOAD SUPPORT William B. Cast, Parlkville, Mo.

Application December 3, 1938, Serial No. 243,681

6 Claims. (Cl. 228-37) The primary object of my invention is to pro- Ordinarily an embodiment of my invention will duce a collapsible stepladder of rigid and subrequire the use of two of the units, which I have stantial construction primarily available as an described above, arranged in parallel vertical article of kitchen furniture so dimensioned as to planes and connected by load-receiving elements be comfortably available as a stool, the construcsuch as steps I6 which are secured to and ex- 5 tion being such that, although readily and very tended between the links II in the same horicompactly foldable, it will nevertheless be sub zontal plane. Conveniently, these links may be stantial and stable under applied loads. made of angle iron, the lower links having their When the invention is understood, it will be horizontal arms at the lower edges of the vertical 10 immediately apparent that its fundamental feaarms and the upper links II, II having their 10 ture may be utilized as a "collapsible frame-work horizontal arms at the upper edges of their vertifor various purposes. cal arms.

The accompanying drawings illustrate my in- In embodiments of my invention in which there vention as incorporated in a three-step step are links II intermediate the lowest link II and ladder, the upper step of which is available as a the links III I, it appears to be necessary, so 5 seat. far as I have been able to discover, that the Fig. 1 is a vertical section of an embodiment spacer I 4 shall be closely subjacent the links of my invention with the parts extended in posi- I I-I I' and that it be Very careful y proportioned tion for support of applied loads; and positioned in order to insure a folding of the Fig. 2 a vertical section showing the parts in leg I3 into parallelism and contact with the ad- 20 collapsed or folded position; jacent upright I0 while at the same'time being Fig. 3 a vertical section of a modification with so controlled that in projected position the lower the parts'extended; and end of upright Ill shall occupy the position noted Fig. 4 shows the collapsed relation of the parts above. As shown in Figs. 3 and 4, the desired shown in Fig. 3. nestability of parts may be obtained by properly 25 The fundamental combination of my invention shaping spacers I4. comprises two parallel uprights orstiles I0, I5, I have found that the desired ends may be at least one of which is a load-supporting memattained by proportioning the parts as shown in ber, connected by parallel links II, II, in desired the drawings, the spacer I4 being pivoted at IT number, at least one of which is long enough to to leg I3 and at I8 to the adjacent upright I0, 30 provide an extension II' projected beyond the the spacing between pivot I5 of the aforesaid vertical uprights Ill, and to which is pivoted, at upright I0 and pivot I8 being considerably less I2 at a point substantially spaced from the pivot than the spacing between pivots I2 and ll. of the adjacent upright, a supporting leg I3 con- By this arrangement, the steps I6, carried by nected by a spacer I4 with one of the uprights I0, the lower links II, may be considerably wider 35 most conveniently the adjacent upright Ill, as than the length of the links with the excess shown in Figs. 1 and 2, but possible as shown in width projected toward leg I3, without inter- Figs. 3 and 4. fering with the movement of the spacer I4 to Each of the links II is pivotally connected to a collapsed position, with the leg I3 brought par- 40 uprights ID at I5, I5 to form the well known allel to and in contact with the adjacent upright 40 parallel link structure. II], as is clearly indicated in Figs. 2 and 4.

The leg I3, to be effective to thoroughly stabi- In order to brace the structure in extended lize the structure when in extended position, p siti n, I se ure to the inn r pr lo a pla should have its lower end spaced considerably- 9 av n a fing r I9 in p siti n t e n a ed more distant from the lower end of the adjacent by the adjacent link II, when the pa ts are e 45 upright I 0 than the spacing between the upper tended, to prevent further swinging movement ends of that upright Ill and leg I3, and the lower of the link I I. Ordinarily only O e of these Stops end of leg I3, when projected, should lie beyond is required in connection with each unit, as indithe vertical plane of the end of the projected cated, although it will bereadily understood that portion II' to which the upper end of the leg I3 such a s p a e provided for each link II i so is connected but, in order that the most compact desired. folded relationship may be automatically at- It will also be understood that instead of the tained, the spacer I 4 must be so positioned and stops I 9, I9 being carried by the inner upright Ill proportioned that the desired ends may be in position to limit downward movement of a attained. link II relative to inner upright ID, a similar 55 that upright relative to one of the links H.

Where, as in the stepladder illustrated, two of the collapsible structures which I have described are used, cross bracing is obtained by an X-brace 20 extending from the lower end of one of the uprights IU of one of the units to the corresponding upright IU of the other unit; and by an X-brace 2| extending between the two legs 13, preferably below the pivots I1.

I claim as my invention:

1. A collapsible load-supporting structure comprising a pair of parallel uprights, at least one of which is ground engaging, two or more parallel horizontal links pivotally connected to and spacing said uprights with an upper one of said horizontal links projected beyond its pivotal connection with one of said uprights, a leg pivotally suspended from the projected end of said lastmentioned horizontal link at a point substantially spaced from the pivotal point of the next adjacent upright, a spacer pivoted to said leg and to one of said pair of uprights in such relation that the structure may be collapsed to substantial parallelisms, and stop means arranged to limit expansive movement of the parts.

2. A collapsible load-supporting structure comprising two parallel units each of which comprises a pair of parallel uprights, at least one of which is ground engaging, two or more parallel horizontal links pivotally connected to and spacing said uprights, with an upper one of said horizontal links projected beyond its pivotal connection with one of said uprights, a leg pivotally suspended from the projected end of said lastrnentioned horizontal link at a point substantially spaced from the pivotal point of the next adjacent upright, and a spacer pivoted to said leg and to one of said pair of uprights in such relation that the structure may be collapsed to substantial parallelisms, load-receiving elements connecting the horizontal links in horizontal pairs, and stop means arranged to limit expansive movement of the parts.

3. A collapsible seat and ladder structure, comprising two parallel units, each of which comprises a pair of parallel uprights, two or more parallel horizontal links pivotally connected to and spacing said uprights with the upper one of said horizontal links projected beyond its pivotal connection with one of said uprights, a leg pivotally suspended from the projected end of said last-mentioned horizontal link at a point substantially spaced from the pivotal point of the next adjacent upright and a spacer pivoted to said leg and one of said uprights in such relation that the structure may be collapsed to substantial parallelisms; steps connecting links in horizontal pairs, the upper step supported by the two projected links being broader than a subjacent step, and means for limiting expansion movement of the parts.

4. In a collapsible load-supporting structure, a

pair of spaced units each including a spaced pair of parallel members, a plurality of parallel links pivotally connected with said parallel members with a selected link projected beyond its pivotal connection with one of said members, a leg member pivotally connected with said projected portion at a point substantially spaced from the pivotal point of the next adjacent of the parallel members, a spacer pivoted to the leg member and to one of said parallel members in such relation that all of said members may be collapsed in substantially close para1lelisms,a plurality of parallel elements connecting the links of the two units in pairs and stop means arranged to limit expansive movement of said members.

5. A collapsible load-supporting structure including spaced pairs of parallel members, a plurality of parallel links pivotally connecting said parallel members in pairs, including means laterally spacing the parallel members of the respective pairs and with two selected links projected beyond their pivotal connection with corresponding members of the respective pairs, leg members pivotally connected with said projected links at points substantially spaced from the pivot of the next adjacent one of the parallel members, a spacer pivoted to one leg member and to one of said parallel members in such relation that said parallel members may be collapsed in substantially close parallelism with the leg members, and stop means arranged to limit expansive movement of said members.

6. A collapsible load-supporting structure, comprising a pair of uprights, at least one of which is ground engaging, two or more parallel horizontal links pivotally connected to and spacing said uprights with an upper one of said horizontal links projected beyond its pivotal connection with one of said uprights, a leg pivotally suspended from the projected end of said last-mentioned horizontal link at a point substantially spaced from the pivotal point of the next adjacent upright, a spacer pivoted to said leg and to one of said pair of vertical links in such relation that the structure may be collapsed to substantial parallelisms, and stop means carried by one of the, uprights and projected into the expansive path of movement of one of the horizontal links to limit expansive movement of the structure.

WILLIAM B. CAST- 

